Physical oceanography from eight Seaglider missions in the Mediterranean Sea, Eastern Basin

In 2008, the Oceanography Center at the University of Cyprus acquired two underwater gliders in the framework of a nationally-managed infrastructure upgrade program. The gliders were purchased from the Seaglider Fabrication Center at the University of Washington. Both gliders are rated to 1000 m and carry a typical sensor payload: non-pumped conductivity-temperature-depth sensors (CTD), a dissolved oxygen sensor, an optical triplet to measure optical backscatter at 400 nm, 700 nm, and chlorophyll-a fluorescence. Since March of 2009, the gliders have been used in a long-term observing program of the Cypriot EEZ, and by September 2015, have covered more than 15300 km over ground and 3500 dive cycles in 940 glider days. Butterfly patterns have been flown in two configurations, either on the western or eastern side of the EEZ south of Cyprus. The glider endurance lines criss-cross the region in order to more accurately locate and investigate the mesoscale structures south of Cyprus, and in particular the Cyprus eddy which is often the dominant feature. Based on the near real time observations, the glider mission was sometimes altered in order to more fully sample the Cyprus eddy, or to locate its center or extent. A summary of the raw and processed data collected, and the quality control procedures are presented, in order for future users to take advantage of this unique data set.

Distribution of planktonic foraminifera in surface sediments of the Mediterranean Sea

The Mediterranean Sea is a partillay isolated ocean where excess evaporation over precipitation results in large east to west gradients in temperature and salinity. Recent planktonic foraminiferal distributions have been examined in 66 surface sediment samples from the Mediterranean Sea. In addition to mapping the frequency distribution of 16 species, the faunal data has been subjected to cluster analysis, factor analysis and species diversity analysis. The clustering of species yields assemblages that are clearly temperature related. A warm assemblage contains both tropical and subtropical elements, while the cool assemblage can be subdivided into cool-subtropical, transitional and polar-subpolar groupings. Factor analysis is used to delineate the geographic distribution of four faunal assemblages. Factor 1 is a tropical-subtropical assemblage dominated by Globigerinoiden ruber. It has its highest values in the warmer eastern basin. Transitional species (Globorotalia inflata and Globigerina bulloides) dominate factor 2 with highest values occurring in the cooler western basin. Factor 3 reflects the distribution of Neogloboquadrina dutertrei and is considered to be salinity dependent. Subpolar species dominate factor 4 (Neoglobuquadrina pachyderma and G. bulloides), with highest values occurring in the northern part of the western basin where cold bottom water is presently being formed. The Shannon-Weiner index of species diversity shows that high diversity exists over much of the western basin and immediately east of the Strait of Sicily. This region is marked by equitable environmental conditions and relatively even distribution of individuals among the species. Conversely, in areas where temperature and salinity values are more extreme, diversity values are lower and the assemblages are dominated by one or two species.